How to Build a Deck on the 2nd Story of Your House

Nathaniel Miller

Are you looking for a way to add entertaining space to your existing home? Maybe you want a private nook overlooking the mountains or lake that are situated next to your home?

A second story deck installation

Regardless of your reason for wanting to add a second story deck to your home, it may seem a daunting or insurmountable task if your carpentry skills are limited. With a little planning, you can build a functional beautiful deck on the second story of your house.


For extra support, you can tie the deck into your existing ceiling joists by simply running two support joists from the edge of the deck to a hole in the roof where you screw the ceiling joists into the support.


Do not build your deck too high off of the ground. As your are mounting the deck on wooden support posts, the posts will be prone to twisting if they are too tall.

  1. Pick the location for your second story deck based on obstacles at ground level, convenient access, and second story entrances. Your location will also determine the dimensions of the deck itself, so take measurements of the length and width of the chosen area and then design your deck frame around these dimensions.

  2. Layout the length and width dimensions next to the house in the location of the future deck and mark the four corners and the midpoint of each side. These will be the locations of your 6 inch by 6 inch support posts. Use the auger to drill 4 foot deep holes in which to slip the bottom of the 6 inch by 6 inch posts. It is up to you how high your deck extends onto the second story, however a typical height is 8-9 feet. Fill each hole partway up with DRY Quikrete concrete mix and then drop the posts in allowing the desired height level of support post extend above ground level. Use a level to make sure each post is plumb and then fill in around the posts with soil and the remaining concrete. Let this setup for at least 24 hours before working on the posts.

  3. Build the frame of the deck on the ground by bolting four boards into a square or rectangle the size of the projected deck. Install crosspieces throughout the frame every two feet to insure a strong base on which to lay your flooring. Using volunteers or a small crane, hoist the boxed in frame on top of your support posts and attach by screwing the lag screws through the frame into the support posts.

  4. Build the deck flooring by laying down the treated decking boards parallel to one another on top of the elevated box frame and screwing down tight with the wood screws. Install the railing kit according to the manufacturer's instructions and determine where a staircase will be installed. Leave the area for the staircase free of railing.

  5. Purchase two staircase runners of the proper height and size for your deck application. Use lag screws to mount the runners to the deck and let the bottom portion of the runners sit on a concrete pad on the ground. Cut left over decking boards into steps for your staircase and mount the steps using wood screws. Start entertaining!